Disable proper (but now unsupported) auth, go ENV variable

This is sad, but this change makes things workable again. Users must now
provide a suitable token via the environment variable `DATALAD_ebrains_token`.

At the moment, this software does not provide any means to obtain such a
token. Users would need to, for example, log into https://query.kg.ebrains.eu
and copy the presented token from the context menu.

Closes datalad#26

datalad_ebrains/kg_query.py

@@ -1,5 +1,6 @@
 import json
 import logging
+import os
 from pathlib import Path
 import requests
 from urllib.parse import quote as urlquote
@@ -95,6 +96,8 @@ def query_kg4dataset(auth_token, dataset_id):
 
 
 def get_token(credential, allow_interactive=True):
+    return os.environ['DATALAD_ebrains_token']
+
     # we ultimately want a token, but it is only valid for a short amount of
     # time, and it has to be obtained via user/pass credentials each time
     user_auth = UserPassword(